WEBVTT ECOND.NOW THE WORK CONTINUES AND IT ISON TO PHASE TWO.THE MASSIVE REBUILD OF THEPRIMARY SPILLWAY REACHES ACRITICAL MILESTONE CAPABLE NOWOF HANDLING RELEASES CLOSE TO200 CUBIC FEET PER SECOND.PROGRESS CLOSELY MONITORED.>> THEY COMPLETED WHAT THEYACCOMPLISHED WITH THEIRDEADLINE.PLUS THE LAKE IS AT 700 FEET ANDTHEY HAVE NO PROBLEMS WITH THATFILLING UP.>> WITH THE WATER LEVEL GOING UPTO THE DAM CREATED ABOUT 2MILLION ACRES OF SPACE.CREWS CAN CONTINUE THEIR WORKTHROUGH THE RAINY SEASON.>> WE ARE GOING TO BE WORKING ONTHIS AS TIME PERMITS.>> THIS WORK IS HALFWAY DONE.THEN IT IS ON TO PHASE TWO WHICHIS FOCUSED ON 700 FEET AT THETOP AND A FINAL PORTION.QUESTION ARE GOING TO DEMOLISHTHIS AND RECONSTRUCTIVE FULLY.IN THE MIDDLE WE ARE GOING TOLOOK AT THIS CONCRETE.>> WHILE OTHERS PHIL WAS CANTAKE YEARS TO CONSTRUCT THIS ONEIS BEING DONE AT A FRACTION OFTHE TIME.HE IS CONFIDENT IN THAT SPILLWAYSTABILITY AS THE CREWS AREWORKING AT SUCH A RAPID RATE.>> MAKE SURE IT IS DONE RIGHT,YOU WANT TO MAKE SURE IT IS DONERIGHT THE FIRST TIME.ONCE WE ARE COMFORTABLE WITH ITAND WE ARE CONFIDENT.SO ARE MANY IN OROVILLE ASWINTER RETURNS.>> AFTER THE FAILURE OF THESPILLWAY I GUARANTEE THEY ARE

California state officials said small cracks that have appeared in the brand new concrete spillway at Oroville Dam were expected and do not pose a threat.

KQED radio of San Francisco reported Tuesday that previously undisclosed letters show federal regulators asked Department of Water Resources officials to explain the hairline cracks on the dam's new massive concrete flood-control chute.

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In an October letter, the Federal Energy Regulatory Commission also asked water officials what, if any, steps might be required to address the issue, as written by the Associated Press.

A hole in the main spillway was discovered in February, leading water officials to shut off outflows from Lake Oroville in an effort to limit erosion damage on the concrete spillway. However, continued rains filled up the lake and eventually spilled over the emergency spillway, which then was in danger of failing.

That led to emergency responders evacuating more than 180,000 people near Lake Oroville as it was feared the area could flood if the emergency spillway gave way. Fortunately, the crisis was averted as water levels subsided at the lake.

With the completion of Phase 1, which has rebuilt and strengthened 2,270 feet of the chute, the spillway is capable of handling flows from the lake of up to 100,000 cubic feet per second.

Lake Oroville stands at 695 feet, which leaves 2.2 million acre-feet of space for the upcoming winter months.

Kiewit, the company awarded with the contract to rebuild the spillway, had more than 600 workers on the project, who have put in more than 720,000 man hours since May to complete Phase 1 on time.

Department of Water Resources

Construction of the secant pile wall, or cut-off wall, downhill from the emergency spillway is scheduled to be completed by the end of January. It is 50 percent complete as of Wednesday.

Work will continue through the winter and into next year to reconstruct the top 730 feet of spillway and the middle section of the spillway, as part of Phase 2, which is scheduled to be completed Nov. 1, 2018.